Various types of apparatus have been employed to move or transfer articles, such as containers, goods, etc., along a processing path for inspection, filling, treating, working and the like.
U.S. Pat. No. 1,629,616 issued May 24, 1927, to Fink; U.S. Pat. No. 4,605,047 issued Aug. 12, 1986, to Bausch et al and U.S. Pat. No. 4,538,489 issued Sept. 3, 1985, to Takano illustrate use of feed screws to move containers relative to one or more work stations. In the Fink and Tokano patents, the feed screws rotate in a stationary position relative to the work station. In the Bausch et al patent, opposing feed screws are pivoted toward and away from the containers in a direction transverse to the direction of advancement of the containers to allow them to be weighed. By withdrawing (pivoting) the feed screws away from and out of engagement with the containers, the containers are maintained in a temporary stationary mode or dwell at the weigh stations.
U.S. Pat. No. 2,922,454 issued Jul. 18, 1961, to Elphee employs a reciprocating slide having inflatable grippers to hold opposite sides of the containers as they are carried by the slide. During advancement of the slide toward the containers, a knife on the slide trims the bottoms of the containers. The grippers are then inflated to grip the trimmed containers and the slide is retracted to carry the containers to an unload station where the grippers are deflated to release the containers.
U.S. Pat. Nos. 2,156,105 issued Apr. 25, 1939; 2,219,809 issued Oct. 29, 1940; 2,923,395 issued Feb. 2, 1960 and 3,652,369 issued Mar. 28, 1972 also disclose use of one or more rotatable feed screws, which are mounted on a stationary base, to feed articles or goods along a processing path.